last year's tainted presidential election. so growing challenges here, both on the security front and on the political front, brian. >> thank you for all of it, john yang in kabul, afghanistan, for us tonight. it has happened again, just south of the u.s. border in the fierce fight between the drug cartels and the mexican government. another journalist has been killed sending a chilling message about how journalist cover the dangerous and violent war on drugs. nbc's mark potter has been reporting exclusively on the war next door to the u.s. he has more tonight on this latest round and a deadly campaign of intimidation. >> reporter: at a dusty funeral over the weekend in juarez, mexico, local journalist mourn the loss of one of their own, an intern at the city's newspaper. 21 year old louise santiago, a photographer, was shot and killed in his car outside a busy shopping center in broad daylight last week. another intern was also shot but survived the attack.